1. Field of the Invention
The present invention relates to a non-volatile memory based storage system and its writing method and, more particularly, to a non-volatile memory based storage system capable of directly overwriting without using redundancy and its method, so as to increase the data access efficiency.
2. Description of Related Art
Typically, an erasing operation for deleting a previously recorded data is required prior to writing data into a flash memory. Thus, a relatively long period of time is required for data writing. This is a drawback of the flash memory. Therefore, there is a need to develop a non-volatile memory capable of being overwritten without the erasing operation. It is envisaged that such non-volatile memory can increase an access efficiency of data.
For writing data into the flash memory, a plurality of blocks in the flash memory are employed as a writing unit. Generally, several bytes at the end of each block is taken as a redundancy field for recording a data writing status of the block and information related to other blocks. As such, it is required to check the redundancy of a target block prior to writing data into the same, resulting in an increase of writing time. Furthermore, the available space for writing data into a block is undesirably reduced because the redundancy occupies a portion of the limited storage space of each block to be written.
Therefore, it is desirable to provide a novel non-volatile memory based storage system capable of directly overwriting without using redundancy and its writing method in order to mitigate and/or obviate the aforementioned problem.